A curable polyorganosiloxane composition which cures by an addition reaction has been known to provide a rubbery cured product excellent in heat resistance, weather resistance, electric insulation, and has been widely used in various fields. Among these, it has been attracted attention in the fields of automobile and semiconductor fields, and in these fields, extremely strict reliability has been required for the purpose of uses thereof, and as one of the requirements, there is required to have cold resistance which can endure the use at a cold district or low-temperature environment.
It has been known to introduce a phenyl group into a base polymer to improve cold resistance (Patent Literature 1). It has also been known to formulate an organopolysiloxane having a resinous structure (Patent Literature 2).